It is a really nice player. From the solid aluminum housing, the good display and all the features it offers, there are few competitors that can match this.
I have had mine for about 3 weeks now and I'm quite happy.

Sound quality: I don't have a Sansa Fuze so I can only compare to my old Samsung T7. For me the sound quality is amazing and I love the EQ Presets.
Concert hall really sounds like a Concert hall.
According to a german magazine, all tested Samsung players featured an above average signal quality. Signal quality was measured scientifically and it is a category where Samsung shines.

Firmware issues: Mine hangs up once in a while but that it is not that often and so far I don't have any other issues.